Dental articulators have been taught for many years and are in wide spread use all over the world and designs range from a simple throw-away version to highly complicated mechanisms encluding electronically controlled jacks and other costly devices costing thousand of dollars.
Several types of articulators are known. One common type is the axle and track articulator manufactured by Hanau Engineering Company. An axle and track has an upper frame and a lower frame, with slots or tracks on the lower frame carrying an axle removably attached to the upper frame.
A second type of articulator is the articulator-condyle or "arcon" type. Arcon artiulators are characterized by a lower frame carrying a pair of condyle balls and an upper frame having guides which receive the condyles and permit the upper frame to pivot and slide on the condyle and move to closely simulate human jaw movements.
One important characteristic of a dental articlulator is the ability to closely simulate the actual centrix, lateral and protrusive jaw movements of the patient in order that the prosthodonist may produce a comfortable and effective dental prosthesis.
Even though the prior art is quite extensive, many problems still exist in the art which the present invention addresses.
One problem which exists in many models is accessibility which is addressed in different manners such as U.S. Pat. No. 4,290,754 which provides for a single, slender arm or support post for the condylar mechanisms which helps in reaching the back section of the teeth models however the incisor guide pin is still in front of the anterior teeth causing an obstruction. U.S. Pat. No. 4,854,868 addresses this problem by providing the incisor guide pin in the form of a horizontal U but still leaves the anterior teeth in an awkward position to be reached by the technician.
Another problem is mounting the models in the articulator so that they can be removed in the same relationship and a number of complicated means are taught such as U.S. Pat. No. 4,169,314 that requires a threaded aperture embedded into the base of the cast. U.S. Pat. No. 4,744,751 teaches a mechanical apparatus which requires two removable fixtures attached to the articulator with additional orientation means.
Yet another problem encountered in most articulators is the lack of the ability to completely remove the top model from the lower model without disassembling the device.
Still another inherent problem especially in the arcon style of articulators is the drawback of the large distance between the two hinge joints locked at the lateral axis. U.S. Pat. No. 4,536,161 attempts to solve this problem by a complicated spring, cam and cam follower arrangement between the pivot arm and the base.